Drafting attachment for scales



Feb. 13, 1940.

J. B. CLERKE DRAFTING ATTACHMENT FOR SCALES Filed April 26, 1958 a 16k 9y 16 INVENTOR BY W fiORNEY tion of a draftingattachr'nent to Patented Fch13, 1940 I nitAFT NG', ATTACHMENT "FOR- some Jo'hn s. .Cl erk e;Springfield Gardens N. Y, c Application April 26, 193s,seri i 'naizoasoaThis invention relates to new and u'seful improvements in a draftingattachme'ntfor topo graphical and similar drawing. 5 The invention hasforanobject the- 'construca triangular the center of a protractor. andvarious distances measured 01f without excessive precaution- Theinvention contemplates constructing the v attachment in a manner so thatitma'y be'turned positions on thetriangular around to different :9Claims." (01.33415) holding the member it in variousadjustedI-p'ositions on the scale and is conti olled'with a knob I3. I

The scale ii is of standard construction. 'Itiis ofequilateral{triangular shape and on the center I scale is provided scaleso that different rulings on the scale may'be used. v 1

Still further the inventionproposes the provi 'sion of Vernier meansassociated with the device I arm. Thisinturned end portion lil -isextended by which it'may be properly adjusted to thezero position of anyone otthe'rulings on the scale.-.

Still further the invention propo'sesan ar-- rangement byz'whichtheCattachment: may. be locked in position on the scale. o For furthercomprehension of the -"invention;..

and'of the objects and'advantages thereof, r'eier- 7 ing. portion w encewill be had' to the followingfdescri-ption and" accompanying. drawing,and toithe appended ;claims in which the various novel features of theinvention are more particularly set'forth.

In the accompanying drawingforminga-material part of'this disclosure:

Fig. 1 is a fragmentary. perspective of. a... triangular. scale with adrafting attachment, ac-,,,v O the" arms of-the tubular member l'fi'jatareas so as I cording tothis invention, engaged thereon. i

drawing and similar drawing,-

Fig. 2 is a fragmentary plan view of'Fig, 1.

Fig. 3 is'a fragmentary sectional .viewtaken on form of the invention..i Fig. 8 is an Bnd'VieW of Fig. '7.

The drafting attachment according to this invention, comprises anequilateral triangularly shaped tubular member). adapted to be slipped.upon'either end portion ofan equilateral triangu- 7 An indication markin the form of a lar scale H.

a-.protractor in nal view similarto Fig. 3,,but

Fig.4 showing the in use on a triangular scale" for' topographicalmember"! 0- is supported by three fingers i5? which arewelded, brazed,soldered or of 'metal which is bent into equilateraltriangular 1 .sh'apeand which has its ends secured together by the a'djacent side arm theScale S aged into the triangular mem-g bery v line of each of the sidestudinal groove lie extending the I full length. Along each o'fthe edgesof each of the sidesthe with ruled scale markings 1 l I is formed from astrip The tubular member ill an'inturnedend portion w forming part ofits I bottom'arm, engaging over andwelded'ybrazed, soldered "or in "anyother manner" securely attached to an extended portion momma-e adjacent.

from thebotto'marm iil of the tubular member! 1 This bottom armisconstructed wider' than, the- 7 other arms .onlone side so that thereis a project v I ofmember lfl' and thev' jacent edge of' the scale IIwhen the end porti'o its center point is aligned'with the-inside edgeoff A web' memberi 5 outside of the triangular a yi er manner securelyattached to the inner faces; of-

to-extend into the grooves H? to the inner edges" of the-arms, butclearing the sides of thelgrooves. J

.view showing another small aperture I2 isassociated with oneside arm'of the member; ID and isadapted to'be aligned .i m le I l'.

large opening i l through which I 16 3.01 theshankpasses.

Washers l8 are mounted upon theshank 1-6? on" "the 'scalei I along theaxis. ;ble of beingturned to move the; tubular member,

. justment. The member In Fig. 4 a protractor 26), to be a scale.

; Theknob i3 is secured to rotative through the web 15.

when the attachment isengaged uponthe' end"of I ashankflfi which is!"The webifl5 has and.

areducedporti on' Lock friction or ,plain.

oDDOsitesides of the Web I5 and serve to fliQ" tionallyhold the shank 46in' position on the web. j The axis'of shank it is concentric with theaxis .of' the scale "and its innerportion lfi 'fis comj-. pletely'threaded and is adapted to threadedly engageeither fixed bushing i9 setintoboth. ends of The knob I3 is capa- Hi forward oi.1earwa1"ds and thustthevernier adof the scale to be used as shown in Fig.2.

used in conjunc-.

tionwith tubular member I9, is illustrated. For

simple accuracy. in drawing; this protractor is a. 54

is formed with a longi'-- .s

The-'-aperture i2 is located-in 6 portion 1%,- I il and lfi 'of thebottom armfso that i 9 should be moved 'to properly align the opening 12with the ,0 "linestraight edge, i. e.

. o'rf the equivalent,

of the markings on tractor, with the longitudinal center line of the Ilarge, light-weight,

sheet with its center semi-circular non-metallic located in the middleof, the the diameter of the curved edge, whichcurved edge is linedch inshort 15-. minute radial lines, the 30-minute lines being a littlelonger, the degreelines still a-little longer, the 5-degree lines stillalittle longer, degree lines' alittlelonger and numbered in two rows;,the outer row, preferably marked in red numbers, beginning at O, at theright endof .the diameter and increasing by tens, counterclockwise, toeter; the inner row, black numbers, from 360 diameter and decreasing by180 at the. right end of thediameter. metallic plate 232 with'a. smallarea turned over to reinforce the the same size as aperture l2, in thescale attach ment, and located at the center of the protractor, is.fastened to the 'protractor. used by engaging a pintle through theopening [2 and through, the opening of the pr'otractor. In thispositionof the parts the beginning of the rulings on the scale l lto be used isexactly at the center of the ,protracton. It is then possible to pivotthe scale angularly about the pintle through opening -2 i of theprotractor and opening 52 in the scale attachment and distances may beaccurately measured off from the center of the protra'ctor 20 along thescale at reference angles or azimuths.., turned clockwise, from g agiven or sighted point. Detent 30, in Fig. 4, is a short semit'ensclockwise to cylindlically shaped metallic member which. is

to a thin metallic plate 3!. The. diameter of the detent is the same asthev diameter of the groove II in-the scale H so' as tobe capable offitting snuglytherein. The plate, 3i isformed with semi-circularextensions on both. ends permitting the plate to be riveted to theprotractorg. A det'ent 35! is secured by rivets, to the protractor 28,just inside the 360 side'of the'proe securely attached detent spacedhalf the width of the side of the scale: from, and parallel to, the edgeof the protracto'r 2i! so that the bottom groove in scale H I may besetover the detent, thus keeping the edge 'protractor but the edge of thescale, being used,-

yofthe scale H at the edge of protractor 253 while angles between and360.

ztgthe scale it is lifted from detent tfl'and swung independently aroundto place the scale off of the contiguous with the other half of theprotractors edge in -which position a pencil point, or'other recorder,"may be injected between these edges,

ithereby recording the desired distance at the de-v sired angle. I i t IU I In Fig. 5' a modification of the invention has been disclosed whichdistinguishes from the prior.

'form in the provision of a locking element for "holding the tubularmember locked-in various positions on the scale. theinvention there is ascrew engages through the-shank it of the screw/25 has a head 26 bywhich it may be 25 which threadedly turned; The inner end 25 of thescrew is adapted to abut against the base of the recess in the bushing19. In. other respects this form of the invention is similar to theprevious form. When the screw 25aabuts against the-baseoi the recess andthe 10-" is adapted to pass 180 at the left end of the diam beingpreferably marked in I at the left end of the A thin center opening 2!,which is exactly scales with 0 at both ends of each side. The attachmentis l i with or withoutth'e protractor claim as new, and desire Accordingto this form of The outer end a spring lock 32, pivoted at 33 in placeof the web and vernier attachments.

welded to the free end of the spring lock 32- and j through a' smallaperture in the side arm of member 10 and'engage in arecess 3G in thescale I l, adapted to hold the small aperture E2 in the bottomarmaligned with the 0 line of the ruling, o-f the scale being used.

A short pin 34; is

, The bottom arm N of member may be made symmetrical about its centerline AA that is,. it would be a separate piece of metal provided.

with inturned end portions W andprojecting portions W with smallapertures l2 at both ends,

and both side arms place of the web and Vernier attachmentsso as havingspring locks 32 i to be able to permit the use of this device on It isto be understood that the size of the triangularscale andof theprotractor may vary and the scale and protractor anchor devices may be.

of any suitable materialand shape andused for topographical or similardrawing.

While I have'illustrated and described the pre- 'ierred'embodiments ofmy invention, it is to be understood that I donut limit myself to thepre-' cise constructions-hereini disclosed.and the right isireservedtoall changes and modifications coming within the scope of" theinvention as defined in the appended claims.

Having thus described to secure by United States Letters Patent is:

my invention, what i 1. A draitingiattachment for topographical andflsimilar-drawing, comprising atriang'ularlynshaped tubular member adaptedto be slipped upon either end portionof. a' triangular vscalejanindication 40" tom arm of said membergadaptedptobealigned with thezeromark-of any'oneof the rulings of. I

mark in theiormof asmalliaperture inthe'botsaid scale, and vernier meansfor holding saith metallic material arm withpart ofthe cured to theother end, extended from the 'adjaje cent side arm, said bottom arm,anditheother. turning it simultaneously with protractor 28 for Forangles be-.

part of its extension, being member in various adjusted..-positions',onsaid M .scale,saidtubularmember"comprising a stripof"bent'into'triangular shape and", having one o'fits ends extendedfromxthe bottom extension bent overand se- 501; widerthan the adja.-.. 1

cent'side-arm, has agprojection past the inner edge of the adjacent sidearm, to-provide mate: rial for the indication marking, and saidindica:

tion marking comprising a small aperture in said projection located."so-"thatits center point i's aligned with the inside edge of theadjacent side" arm and with the'adjacent edge of the scale when the,endportion of the scale is engaged into the u ular member. l U

, 2." A drafting attachment for topographical v I similardrawing,comprising'a-triangularlyshaped tubular member adapted to beslipped upon either;

end portion of a triangular scale; anindication mark in theform of asmall-aperture in the bot, tom'arm of said, member adapted to bealignedr with the zero mark-oi any, one of-the'rulin'g'sot. "1 saidscale, 'and- Vernier means for holding said.-

member in various adjusted positions onfs'aid:

scale, said Vern er means comprising .awebse cured-'to said tubularmember, ashankireduced' j and rotative through'said web and haVing an Jouterknob by which it may be turned, thefinner portion of 1 saidshank-being threadedl-yconnec 7 triangular scales tive'with a fi'xedbushing in either end-of said 3. A drafting attachment for topographicaland similar drawing comprising a triangularly shaped tubular-memberadapted to be slipped upon either end portion of atriangular' scale, anindication mark in the formtof a small aperture in the bottom arm ofsaid member, adapted to be aligned with the zero mark of'any one of .therulings of said scale, and vernier means for holdingsaid member invarious adjusted positions on said scale, comprising also a web securedto said tubular member, a shank reduced-and rotative through saidwebandzhaving an outer knob by which it :may be turned, the innerportion of said shank being threadedlyconnective with a fixed bushing ineither endof said triangular scale, said bushings to be securelyengagedqinto both ends and along the axis of the triangularscale andeach having. a-threaded opening along its axis for receivingthethreaded-end of the shank.

,4. Adraftingattachment for topographical and similar drawing,.comprising a triangularly shaped tubular member adapted to be slipped;upon either :end portiongzof a triangular scale, an indication mark inthe form of a small aperture in the bot posite sides of the web forfrictionally holding said shank, and spreading the pressure'to the threearms.

5. A drafting attachment for topographical and similar drawing,comprising a triangularly shaped tubular member adapted to'be slippedupon either end portion of a triangular scale, an indication mark in theform' of a small aperture in the bottom arm of said member adapted to bealigned with the zero mark of any one of the rulings'of said scale, andvernier means for holding said member in various adjusted positions onsaid scale, comprising also a web secured to said tubular member, ashank reduced and rotative through said web and having an outer knob bywhich it may be turned,'the inner portion of said shank being threadedlyconnective with a fixed bush ingin either end of said triangular scale,and washers mounted on said shank and engaging opposite sides of the webfor frictionally holding said shank and spreading the pressure to thethree arms, said web having a slightly larger opening through-which thereduced shank passes so as to allow for slight discrepancies inalignment of the axes, and permitting the shank to assume variouspositions to readily be threadedly engagedinto'the bushing in either endof said triangular scale in all turned positionsi of said tubular memberon the scale.

6. A drafting attachment for topographical and similar drawing,comprising a triangularlyv shaped tubular'member adapted to be slippedupon either *end portion of a triangular scale, an indication mark inthe form of a small aperture in the bottom arm of said member adapted tobe aligned with the zero mark of any one of the rulings of .said scale,and vernier means for holding said member in various adjusted ,positionson said scale, comprising also a web se-- cured to said tubular member,a shank reduced and rotatative through said Web and having an outerknobby which it may be turned, the inner portion of said shank beingthreadedly. connec I tive' with a fixed bushing in either end of saidtriangular scale. and washers mounted onsaid shank andengaging oppositesides of theweb for frictionally holding said shank and spreading thepressure. to the three arms, said web having a slightly larger openingthrough which the reduced shank passes so as to allow for slightdiscrepancies in alignmentv of the axes, and permitting the shank toassume various positions to readily be threadedlyengaged into thebushing in either end of said triangular scale in all turned positionsof said tubular member on the scale, and a screw threadedly engagedthrough and on axis of said shank and adapted to abut against the baseof the recess in the receptive bushing of said triangular scale tofixedly hold the shank in the correct position, said screw beingturnednby a small knob secured to the outer end thereof.

7. A device of the class described, comprising ,a triangularlyshapedtubular member adapted,

to be slipped upon either end portion of a triangular scale,anindication mark in the form of a small aperture in thebottom arm ofsaid member, adapted to be aligned with the zero mark of any of therulings of said scale, and vernier means for holding said member invarious adjusted positions on said scale, said tubular member comprisinga strip of metallic material bent into triangular shape and having oneof its ends extendedfrom the bottom arm with part of the extension bentover and secured to the other end, extended from the adjacent side arm,

said bottom arm, and the other part of its extension, being wider thanthe adjacent side arm, and having a projection ,pastthe inner edge ofthe adjacent side arm,'to provide material for the indication marking,and said indication marking comprising a small aperture in saidprojection located so that its center point is aligned with the insideedge of the adjacent side arm and with the adjacent edge of the scalewhen the end portion of the scale is engaged into, the tubular member, aprotractor with an aperture at its zero position, so arranged that theaperture of the said triangularly shaped member may conveniently besuperimposed over the aperture of the protractor.

8. A device of the class described, comprising a triangularly shapedtubular member adapted to be slipped upon either end portion of atriangular scale, an indication mark in the form mark of any of therulings of said scale, and vernier means for holding said member invarious adjusted positions on said scale, said tubular member comprisinga strip of metallic material bent into triangular shape and having oneof its ends extended from the bottom arm with part of the .extensionbent over and secured to the other end, extended from the adjacent sidearm, said bottom arm, and the other part of its extension, being widerthan the adjacent side arm, and having a projection past the inner edgeof the adjacent side arm, to provide material for the indicationmarking, and said indication of a small aperture in the bottom arm ofsaid member, adapted to be aligned with the zero marking comprising asmall aperture in said projection located so that its center point isaligned with the inside edge of the adjacent side arm and with theadjacent edge of the scale whenthe end portion of the scale isengagedinto the tubular member, a protractor with. an aperture at itszero position, so arranged that the aperture of the said triangularlyshaped member may conveniently be superimposed over the aperture of theprotractor, a small reinforcing plate secured to the protractor in thevicinity of its zero position, and'part of the reinforcing memberprotruding from the protractor topermit the aperture of the latter to beon the protractor edge.

9. A drafting attachment for conventional triangular scales used inconjunction with a protractor and detents for topographical and similardrawing, comprising a trian-gularly shaped tubu-' lar member adapted tobe slipped upon either end portion of a triangular scale, an indicationmark in the form of a small aperture in the bottom arm of said member,adapted to be aligned with the zero mark of any of the rulings of saidscale, and Vernier means for holding said member in various adjustedpositions on said scale, said tubular member comprising a strip ofmetallic material bent into triangular shape and having one of its endsextended from the bottom arm with part of the extension bent over andsecuredto the other end, extended-:fromthe:adjacent side arm, part ofits extension, being wider than the adjacent side arm, and the inneredge of the adjacent side arm,

having, a projectionv past]; to. provide materialfor the indicationmarking, and;

said bottom arm, and the others:

said indication marking comprising a small aper- I ture in saidprojection located so that its center r point is aligned with themsideedge of the a'd'- jacent side armandwith the adjacentedge'of the scalewhen the end engaged into the tubular member, with an aperture at itszero position,so*arranged of its zero position,

portion of the scale is a protractor tractor edge, detents projectingfrom the vicinity of the straight edge of the protractor said detentsbeing capable of moving the scale .whentheprotractor is turned.

JOHN B. CLER E.

